Benzaldehyde → HCID 4247613, compound

Participants

Reaction Conditions

Reaction Steps

This Example demonstrates the reduction of (3-cyanomethyl-2-phenyl-imidazolidin-1-yl)-acetonitrile (5) with LiAlH4 and protection using benzaldehyde. As shown in Scheme 3, a solution of 1 equivalent of (3-cyanomethyl-2-phenyl-imidazolidin-1-yl)-acetonitrile (5) was added to a solution of 3 equivalents of LiAlH4 in THF at about −30° C. The reaction mixture was warmed to about 20° C. over 80 minutes, whereupon thin-layer chromatography showed complete conversion. The reaction mixture was treated with water (vigorous, exothermic reaction with H2-evolution) and aluminum salts were removed by filtration. Isolation of the amine intermediate 2-[3-(2-Amino-ethyl)-2-phenyl-imidazolidin-1-yl]-ethylamine (8) as a pure compound was not readily achieved. To add protecting groups and allow isolation the amine intermediate (8) was reacted in situ with 2.2 equivalents of benzaldehyde after aqueous quench. After work-up and crystallization from acetonitrile, crystalline benzylidene-(2-{3-[2-(benzylidene-amino)-ethyl]-2-phenyl-imidazolidin-1-yl}-ethyl)-amine (7) was obtained in 32% yield and with a purity of 95.8 area % by gas chromatography.

Provenance & Evidence